Dpdk: dpdk: guest-triggered out-of-bounds walk via vhost indirect descriptor length toctou
Summary
| CVE | CVE-2026-93683 |
|---|---|
| State | PUBLISHED |
| Assigner | redhat |
| Source Priority | CVE Program / NVD first with legacy fallback |
| Published | 2026-10-14 16:17:57 UTC |
| Updated | 2026-10-14 20:13:37 UTC |
| Description | A flaw was found in the DPDK vhost library. When handling a virtio indirect descriptor table, the host reads the table length more than once from guest memory and can allocate a host copy before validating that length. A guest that changes the length between those reads, or that supplies an out-of-range next index on a small host copy in the vDPA relay path, can cause the host vhost process to walk past the validated mapping or heap copy. That can crash or disrupt the vhost process. Out-of-bounds bytes are consumed as descriptor fields for GPA translation and are not returned to the guest as payload. This is a residual issue in the non-contiguous indirect descriptor copy path introduced as part of the CVE-2018-1059 fix. |
Risk And Classification
Primary CVSS: v3.1 6.4 MEDIUM from [email protected]
CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:C/C:L/I:N/A:H
Problem Types: CWE-367 | CWE-367 Time-of-check Time-of-use (TOCTOU) Race Condition
| Version | Source | Type | Score | Severity | Vector |
|---|---|---|---|---|---|
| 3.1 | [email protected] | Secondary | 6.4 | MEDIUM | CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:C/C:L/I:N/A:H |
| 3.1 | CNA | CVSS | 6.4 | MEDIUM | CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:C/C:L/I:N/A:H |
CVSS v3.1 Breakdown
Attack Vector
LocalAttack Complexity
HighPrivileges Required
LowUser Interaction
NoneScope
ChangedConfidentiality
LowIntegrity
NoneAvailability
HighCVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:C/C:L/I:N/A:H
Vendor Declared Affected Products
| Source | Vendor | Product | Version | Platforms |
|---|---|---|---|---|
| CNA | Red Hat | Fast Datapath For RHEL 10 | Not specified | Not specified |
| CNA | Red Hat | Fast Datapath For RHEL 10 | Not specified | Not specified |
| CNA | Red Hat | Fast Datapath For RHEL 8 | Not specified | Not specified |
| CNA | Red Hat | Fast Datapath For RHEL 8 | Not specified | Not specified |
| CNA | Red Hat | Fast Datapath For RHEL 8 | Not specified | Not specified |
| CNA | Red Hat | Fast Datapath For RHEL 8 | Not specified | Not specified |
| CNA | Red Hat | Fast Datapath For RHEL 8 | Not specified | Not specified |
| CNA | Red Hat | Fast Datapath For RHEL 8 | Not specified | Not specified |
| CNA | Red Hat | Fast Datapath For RHEL 8 | Not specified | Not specified |
| CNA | Red Hat | Fast Datapath For RHEL 9 | Not specified | Not specified |
| CNA | Red Hat | Fast Datapath For RHEL 9 | Not specified | Not specified |
| CNA | Red Hat | Fast Datapath For RHEL 9 | Not specified | Not specified |
| CNA | Red Hat | Fast Datapath For RHEL 9 | Not specified | Not specified |
| CNA | Red Hat | Fast Datapath For RHEL 9 | Not specified | Not specified |
| CNA | Red Hat | Fast Datapath For RHEL 9 | Not specified | Not specified |
| CNA | Red Hat | Fast Datapath For RHEL 9 | Not specified | Not specified |
| CNA | Red Hat | Fast Datapath For RHEL 9 | Not specified | Not specified |
| CNA | Red Hat | Red Hat Enterprise Linux 10 | Not specified | Not specified |
| CNA | Red Hat | Red Hat Enterprise Linux 8 | Not specified | Not specified |
| CNA | Red Hat | Red Hat Enterprise Linux 9 | Not specified | Not specified |
| CNA | Red Hat | Red Hat OpenShift Container Platform 4 | Not specified | Not specified |
| CNA | Red Hat | Red Hat OpenShift Container Platform 4 | Not specified | Not specified |
| CNA | Red Hat | Red Hat OpenShift Container Platform 4 | Not specified | Not specified |
| CNA | Red Hat | Red Hat OpenStack Platform 13 Queens | Not specified | Not specified |
References
| Reference | Source | Link | Tags |
|---|---|---|---|
| bugzilla.redhat.com/show_bug.cgi | [email protected] | bugzilla.redhat.com | |
| access.redhat.com/security/cve/CVE-2026-93683 | [email protected] | access.redhat.com | |
| CVE Program record | CVE.ORG | www.cve.org | canonical |
| NVD vulnerability detail | NVD | nvd.nist.gov | canonical, analysis |
Vendor Comments And Credit
Discovery Credit
CNA: Red Hat would like to thank Naseeb Dangi (AOSP Lab @Nankai University) and Xiang Li (AOSP Lab @Nankai University) for reporting this issue. (en)
Additional Advisory Data
| Source | Time | Event |
|---|---|---|
| CNA | 2026-09-18T14:13:34.245Z | Reported to Red Hat. |
| CNA | 2026-10-14T15:03:08.668Z | Made public. |
Workarounds
CNA: No runtime mitigation. QEMU indirect_desc=off does not help: libvhost honours VRING_DESC_F_INDIRECT anyway. Do not expose vhost-user to untrusted guests.
There are currently no legacy QID mappings associated with this CVE.